Airway management in neonates and infants: European Society of Anaesthesiology and Intensive Care and British Journal of Anaesthesia joint guidelines.

Airway management is required during general anaesthesia and is essential for life-threatening conditions such as cardiopulmonary resuscitation. Evidence from recent trials indicates a high incidence of critical events during airway management, especially in neonates or infants. It is important to define the optimal techniques and strategies for airway management in these groups. In this joint European Society of Anaesthesiology and Intensive Care (ESAIC) and British Journal of Anaesthesia (BJA) guideline on airway management in neonates and infants, we present aggregated and evidence-based recommendations to assist clinicians in providing safe and effective medical care. We identified seven main areas of interest for airway management: i) preoperative assessment and preparation; ii) medications; iii) techniques and algorithms; iv) identification and treatment of difficult airways; v) confirmation of tracheal intubation; vi) tracheal extubation, and vii) human factors. Based on these areas, Population, Intervention, Comparison, Outcomes (PICO) questions were derived that guided a structured literature search. GRADE (Grading of Recommendations, Assessment, Development and Evaluation) methodology was used to formulate the recommendations based on those studies included with consideration of their methodological quality (strong '1' or weak '2' recommendation with high 'A', medium 'B' or low 'C' quality of evidence). In summary, we recommend: 1. Use medical history and physical examination to predict difficult airway management (1C). 2. Ensure adequate level of sedation or general anaesthesia during airway management (1B). 3. Administer neuromuscular blocker before tracheal intubation when spontaneous breathing is not necessary (1C). 4. Use a videolaryngoscope with an age-adapted standard blade as first choice for tracheal intubation (1B). 5. Apply apnoeic oxygenation during tracheal intubation in neonates (1B). 6. Consider a supraglottic airway for rescue oxygenation and ventilation when tracheal intubation fails (1B). 7. Limit the number of tracheal intubation attempts (1C). 8. Use a stylet to reinforce and preshape tracheal tubes when hyperangulated videolaryngoscope blades are used and when the larynx is anatomically anterior (1C). 9. Verify intubation is successful with clinical assessment and end-tidal CO2 waveform (1C). 10. Apply high-flow nasal oxygenation, continuous positive airway pressure or nasal intermittent positive pressure ventilation for postextubation respiratory support, when appropriate (1B).

Airway management in neonates and infants: European Society of Anaesthesiology and Intensive Care and British Journal of Anaesthesia joint guidelines.

Airway management is required during general anaesthesia and is essential for life-threatening conditions such as cardiopulmonary resuscitation. Evidence from recent trials indicates a high incidence of critical events during airway management, especially in neonates or infants. It is important to define the optimal techniques and strategies for airway management in these groups. In this joint European Society of Anaesthesiology and Intensive Care (ESAIC) and British Journal of Anaesthesia (BJA) guideline on airway management in neonates and infants, we present aggregated and evidence-based recommendations to assist clinicians in providing safe and effective medical care. We identified seven main areas of interest for airway management: i) preoperative assessment and preparation; ii) medications; iii) techniques and algorithms; iv) identification and treatment of difficult airways; v) confirmation of tracheal intubation; vi) tracheal extubation, and vii) human factors. Based on these areas, Population, Intervention, Comparison, Outcomes (PICO) questions were derived that guided a structured literature search. GRADE (Grading of Recommendations, Assessment, Development and Evaluation) methodology was used to formulate the recommendations based on those studies included with consideration of their methodological quality (strong '1' or weak '2' recommendation with high 'A', medium 'B' or low 'C' quality of evidence). In summary, we recommend: 1. Use medical history and physical examination to predict difficult airway management (1С). 2. Ensure adequate level of sedation or general anaesthesia during airway management (1B). 3. Administer neuromuscular blocker before tracheal intubation when spontaneous breathing is not necessary (1С). 4. Use a videolaryngoscope with an age-adapted standard blade as first choice for tracheal intubation (1B). 5. Apply apnoeic oxygenation during tracheal intubation in neonates (1B). 6. Consider a supraglottic airway for rescue oxygenation and ventilation when tracheal intubation fails (1B). 7. Limit the number of tracheal intubation attempts (1C). 8. Use a stylet to reinforce and preshape tracheal tubes when hyperangulated videolaryngoscope blades are used and when the larynx is anatomically anterior (1C). 9. Verify intubation is successful with clinical assessment and end-tidal CO 2 waveform (1C). 10. Apply high-flow nasal oxygenation, continuous positive airway pressure or nasal intermittent positive pressure ventilation for postextubation respiratory support, when appropriate (1B).

Differences in the epidermal pain threshold between different needle puncture sites.

PURPOSE: Puncture of the skin by a needle, such as for peripheral nerve block or for intravenous or arterial catheter placement, may cause pain to the patient, so that analgesic method may be required to reduce pain caused by needle puncture. Nevertheless, there is little information as to which puncture sites are more painful than the other. METHODS: After obtaining an approval of the study by a research ethics committee and written informed consent from all the participants, we studied 30 volunteers to quantify pain threshold at 13 skin sites of the body, using an algometer. RESULTS: Compared with pain threshold at the cubital fossa (which was regarded as the control value), the relative pain threshold was significantly lower (with clinically meaningful difference) at the lateral carpus (median (interquartile range): 0.66 (0.56-0.73)) and the medial carpus (0.80 (0.73-0.94)); and was significantly higher (with clinically meaningful difference) at the olecranon (2.08 (1.93-2.42)), the forehead (1.59 (1.46-1.74)), the upper shoulder (1.52 (1.38-1.79)), and the dorsal shoulder (1.39 (1.18-1.55)). CONCLUSIONS: We conclude that there are significant differences in pain threshold between different puncture sites. Analgesic method before needle puncture may be required at the sites where the pain threshold is relatively low.

Usefulness of an automatic cuff pressure controller (SmartCuff) in inhibiting gasleakage around the cuff after tracheal intubation: a randomized controlled study.

PURPOSE: Gas leakage around the cuff of a tracheal tube may frequently occur after tracheal intubation and inflation of the cuff. We assessed if the SmartCuff (Smiths Medical Japan, Tokyo, Japan), an automatic cuff pressure controller, would effectively prevent gas leakage. METHODS: Seventy adult patients were allocated randomly to one of two groups. After induction of general anesthesia and tracheal intubation, in one group (Syringe group), a syringe was used to inflate the cuff, until there was no audible gas leakage, at the airway pressure at 20 cmH2O. In the other group (SmartCuff group), the SmartCuff was used to maintain the cuff pressure to be 20 cmH2O. The mechanical ventilation (tidal volume of 8 ml.kg-1 and 12 breaths per min) was started. The incidence and percentage of gas leakage, and the proportion of adequate seal (defined as gas leakage of < 10%) between the groups were compared. RESULTS: The incidence of audible gas leakage was significantly higher in the Syringe group (10 of 35 patients (28%)) than in the SmartCuff group (none of 35 patients (0%)) (P = 0.00046, 95%CI for difference: 15-43%), and the proportion of adequate seal was significantly lower in the Syringe group (19 of 35 patients (54%)) than in the Smart cuff group (33 of 35 patients (94%)) (P = 0.0001, 95% CI for difference: 20-58%). CONCLUSION: Gas leakage may frequently occur after tracheal intubation, and the use of the SmartCuff can effectively maintain the sealing effect of the cuff.

Fibreoptic intubation: a commitment to an indispensable technique.

Recent evidence has shown that fibreoptic intubation is still an indispensable technique for safe management of predicted difficult airways, despite the implementation of new technologies such as videolaryngoscopy. It is therefore our obligation as anaesthesia societies and as practicing anaesthetists to offer this technique to our patients in clearly designated situations.

Preventing difficult facemask ventilation in children: all is well that starts well.

Difficult facemask ventilation at induction of general anaesthesia can trigger hypoxaemia and inadequate ventilation if not immediately identified and adequately treated. For this reason, identification of predisposing conditions before induction of anaesthesia and causes of poor facemask ventilation are critical to avoid the subsequent complications. In a recently published secondary analysis of the Paediatric Difficult Intubation (PeDI) registry, the incidence and risk factors for difficult facemask ventilation in children with difficult tracheal intubation was described, as highlighted in the editorial.

Tracheal tube cuff pressure during anesthesia for robotic-assisted laparoscopic prostatectomy and the efficacy of an automatic cuff pressure controller (SmartCuff): observational studies of 1-sample paired data.

PURPOSE: The cuff pressure of a tracheal tube may increase during robot-assisted laparoscopic surgery for prostatectomy (RALP), which requires pneumoperitoneum in a steep head-down position, but there have been no studies which confirmed this. METHODS: In study 1, we studied how frequently the cuff pressure significantly increased during anesthesia for the RALP. In study 2, we studied if the SmartCuff (Smiths Medical Japan, Tokyo) automatic cuff pressure controller would minimize the changes in the intracuff pressure. With approval of the study by the research ethics committee (approved number: 20115), we measured the cuff pressures in anesthetized patients undergoing RALP and in those undergoing gynecological laparotomy (as a reference cohort), with and without the use of the SmartCuff. RESULTS: In 21 patients undergoing RALP, a clinically meaningful increase (5 cmH2O or greater) was observed in all the 21 patients (P = 0.00; 95% CI for difference: 86-100%), whereas in 23 patients undergoing gynecological laparotomy, a clinically meaningful decrease (5 cmH2O or greater) was observed in 21 of 23 patients (91%, P < 0.0001; 95% CI for difference: 72-99%). With the use of the SmartCuff, there was no significant increase in the incidence of a clinically meaningful change in the intracuff pressure in either cohort. CONCLUSION: The cuff pressure of a tracheal tube would frequently increase markedly in patients undergoing RALP, whereas it would frequently decrease markedly in patients undergoing gynecological laparotomy. The SmartCuff may inhibit the changes in the cuff pressure during anesthesia.

Efficacy of an aerosol suction device Free-100 M in removing aerosols produced by coughing to minimize COVID-19 infection.

PURPOSE: The healthcare workers are at the greatest risk of being exposed to viral infection during airway management of a patient with coronavirus disease 2019 (COVID-19). An air extractor which suctions air around the patient's face would reduce the spread of viral aerosols during coughing, but no study has confirmed this. We assessed whether or not an air extractor reduces the amount of aerosols spreading toward the operator's face, during coughing of simulated patients. METHODS: After obtained approval of the study by a research ethics committee and written informed consent from 20 volunteers (and additional 20 volunteers), we asked each volunteer to lie supine on a table in a positive-pressure management operating room. As a cross-over design, we used an airborne particle counter (Handheld 3016, SGY company, Tokyo) to measure the aerosols approximately 30 cm above the participant's mouth, while the volunteer was coughing, with and without the use of an air extractor Free-100 M (Forest-one, Funabashi), facing the participant's mouth. In another 20 volunteers, the aerosols were measured, while each volunteer was lying supine, without coughing, and without the use of the air extractor. RESULTS: The aerosol count during coughing was significantly lower when the air extractor was used [median: 55 (interquartile range: 15-128)] than when it was not used [73 (44-201)] [p = 0.001, difference: 19 (95%CI: 4-70)]. CONCLUSIONS: The Free-100 M air extractor would reduce, but do not remove all, aerosols produced by coughing of a patient, and thus may reduce the risk of infection of COVID-19.

Remimazolam: a randomized controlled study of its suitability for insertion of a supraglottic airway.

PURPOSE: Loss of motor response to thrusting the jaw forward is a useful indicator for uncomplicated insertion of a supraglottic airway. The aim of this study was to assess the suitability of remimazolam for insertion of a supraglottic airway assessed by loss of response to jaw thrusting. METHODS: Seventy patients, who were scheduled for elective surgeries under general anesthesia, were allocated randomly to one of two groups. In one group (remimazolam group), remimazolam was infused 12 mg kg-1 h-1 (50 mg maximum), and in the other (propofol group), propofol was infused at 120 mg kg-1 h-1 (500 mg maximum). Once the eyelash reflex disappeared, response to jaw thrusting was assessed. Primary outcome measure was the proportion of patients with loss of response to jaw thrusting before reaching the maximum dose of the test drug. We planned an interim analysis (of one time) after 40 patients, using the Pocock adjustment method. RESULTS: From the interim analysis results, the study was stopped after recruitment of 40 patients. Loss of response to jaw thrusting was observed in all of 21 patients (100%) in the propofol group, and in 9 of 19 patients (47%) in the remimazolam group. There was a significant difference in the proportion between the groups (P = 0.0001, 95% CI for difference 30-75%). CONCLUSION: Remimazolam frequently does not inhibit response to jaw thrusting, and thus remimazolam is not a suitable induction agent for uncomplicated insertion of a supraglottic airway unless either a neuromuscular blocking agent or an opioid is co-administered.

Efficacy of a surgical mask during high-flow nasal oxygen therapy in preventing aerosol dispersion: a randomized controlled study.

PURPOSE: It is not clear whether or not high-flow nasal oxygenation used in patients with severe respiratory tract infection, or coughing, increases the risk of infection to the healthcare personnel, and whether or not applying a surgical mask to the patient's face or treating the patient in a negative-pressure room can reduce the risk. METHODS: In a randomized crossover design, we compared in 50 participants receiving high-flow nasal oxygenation, the aerosol counts measured at approximately 20 cm above the participant's mouth in 32 different circumstances (with or without coughing, with or without wearing a surgical mask, at four different flow rates of oxygenation, in a positive- or negative-pressure operating room). RESULTS: In a positive-pressure room, a surgical mask significantly decreased the aerosol counts during coughing (P = 0.0005), or during no coughing (P = 0.009), under high-flow nasal oxygenation (at 60 l.min-1). In the negative-pressure room, the aerosol count was significantly lower than in the positive-pressure room, for all the circumstances (all P < 0.001), and a surgical mask significantly decreased the aerosol counts during coughing (P = 0.047) but not during no coughing (P = 0.60). CONCLUSION: In conclusion, treating a patient in a negative-pressure room, or applying a surgical mask, during high-flow nasal oxygenation (with the flow rate of 60 l.min-1) would inhibit, but would not completely prevent, dispersion of aerosols by coughing.

Efficacy of McGRATH®MAC videolaryngoscope blade 1 for tracheal intubation in small children: a randomized controlled clinical study.

BACKGROUND: Videolaryngoscopes may not be as effective in small children as they are in older children and in adults. The size 1 blade is commercially available for the McGRATH®MAC videolaryngoscope (Covidien, Medtronic, Tokyo, Japan), but its efficacy in comparison with a Macintosh laryngoscope blade 1 is not known. AIM: The main aim of this study was to assess the efficacy of McGrath®MAC blade 1 in comparison with a conventional Macintosh laryngoscope blade 1, in children aged less than 24 months. METHODS: Thirty-eight children aged less than 24 months were randomly allocated to one of two groups, and tracheal intubation was attempted using either a direct laryngoscope with a Macintosh blade 1 or a videolaryngoscope with a McGRATH®MAC blade 1. In another 12 children aged 2-4 years, the same comparisons were made with blade 2. The primary outcome measure was time to tracheal intubation using a size 1 blade. RESULTS: Tracheal intubation took significantly longer with a McGRATH®MAC blade 1 (median (interquartile range): 38.0 (31.8-43.5) s) than with the Macintosh blade 1(27.4 (25.9-29.2) s) (p < 0.0001; median difference (95% CI for the median difference): 10.6 (6.4-14.0) s), mainly due to difficulty in advancing a tube into the trachea. No significant difference was observed for the size 2. CONCLUSIONS: In small children without predicted difficult airways, time to intubate the trachea was significantly longer for a McGRATH®MAC blade 1 than a Macintosh blade 1. CLINICAL TRIAL REGISTRATION: jRCT1032220366.

Efficacy of a gastric tube insertion guide for insertion of a nasogastric tube: a prospective, randomized controlled clinical study.

PURPOSE: We studied whether a newly available gastric tube insertion guide (Fuji Medical, Tokyo, Japan) was effective in insertion of a nasogastric tube. METHODS: Sixty anesthetized patients were randomly allocated to three groups, and we attempted to insert a nasogastric tube with a blind technique (Group B), with the lateral neck pressure (Group L), or with the tube guide (Group G). If the insertion failed in Group B or L, its insertion was attempted with the tube guide. Primary outcome measure was the insertion success rate within 300 s. RESULTS: The success rate in Group G (19 of 20 patients) was significantly higher than Group L (13 of 20 patients) (P = 0.04; 95% confidence intervals for difference: 16-44%), and than Group B (11 of 19 patients) (P = 0.008; 23-50%). In the 15 patients of Groups B and L, in whom insertion had failed, insertion with the tube guide was successful in 14 patients. There was no significant difference in insertion time between the groups, but in patients in whom insertion was successful, it was significantly longer in Group G (median of 147 s) than in Group L (66 s) (P < 0.01) and Group B (46 s) (P < 0.01). Minor complications occurred in 2 patients in Group B, 1 in Group L, and 5 in Group G (P > 0.05). CONCLUSION: We conclude that the gastric tube insertion guide (Fuji Medical, Tokyo, Japan) may be useful when the conventional method of insertion has failed.

Reviewing COVID-19 from an anesthesiologist's perspective in 2022: JA symposium.

The COVID-19 pandemic is ongoing as of September 2022. Since January 2020 when the first case was reported in Japan, the medical community faced a variety of problems both domestically and internationally. It is meaningful to review the impact of COVID-19 from an anesthesiologist's perspective to clarify our policy for future infectious disease outbreaks. In this year's Journal of Anesthesia (JA) symposium, five experts who were deeply involved in the COVID-19 response reviewed the past 2.5 years and made recommendations for potential future pandemics. Anesthesiologists are specialists in airway management and their role in intubating patients with COVID-19 has received much attention. However, they have also played an important backup role in intensive care as critical care physicians and must be more involved in critical care in regular (non-pandemic) times to properly fulfill this role. It is especially important for the Japan Society of Anesthesiologists and JA to quickly disseminate accurate information on unknown infectious diseases to the medical community and wider society. Therefore, it is important to promptly publish papers that are quality-assured through peer review.

Standard of anesthesia care: possible dissociation from recommendations made by clinical practice guidelines.

A medical malpractice lawsuit may be brought against health care providers, if there was a possibility of a negligence, or failure to meet the standard of care. Recently, clinical practice guidelines have increasingly been used as evidence of the standard of care. Nevertheless, it is not clear whether these guidelines can be used as evidence of the standard of care. We carried out a snapshot study to know whether or not there were dissociations between the current standard of anesthesia care and recommendations made by clinical practice guidelines. We asked all the 80 heads of Anesthesiology departments of Japanese public and private Universities, to answer questions related to difficult airway management after induction of anesthesia, postoperative monitoring of breathing, and of the presence or the absence of neuropathy of the lower legs after regional anesthesia. The response rate was 71% (57/80). The majority of anesthesiologists had little experience with front-of-neck access in patient, and responders might frequently make repeated attempts at tracheal intubation. Postoperative monitoring was frequently not routinely performed. In conclusion, this study has shown that there may be various degrees of dissociations between the current standard of anesthesia care and the recommendations made by clinical practice guidelines that had been used as evidence of the standard of care in medical malpractice lawsuit cases in Japan.

Aerosol containment device for airway management of patients with COVID-19: a narrative review.

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), is highly contagious. To protect healthcare workers from infection during airway management, some expert recommendations and guidelines recommended wearing P2/N95 masks, goggles or glasses, glove, face-shields, and gowns as standard personal protective equipment (PPE). Nevertheless, several simulation studies have suggested that the standard PPE may not fully protect healthcare workers. Dr. Hsien Yung Lai introduced an acrylic box ("aerosol box") as a part of PPE during airway management. Since then, several companies and healthcare workers have made their own modified devices ("aerosol containment device"), and the use of such a device has spread worldwide, without being formally assessed for its effectiveness, efficacy and safety. Several simulation studies have indicated that "aerosol containment device" would make tracheal intubation more difficult. In addition, the device would prevent the spread of droplets from a patient, but may increase the risk of healthcare workers being exposed to a higher concentration of viral aerosols. Therefore, the current state of knowledge indicates that an "aerosol containment device" without vacuum mechanism has only limited efficacy in protecting healthcare workers from viral transmission.

Margin of safety for needle puncture of a radial artery.

The radial artery is the preferred site for arterial cannulation because of consistent anatomic accessibility, ease of cannulation, and a low incidence of complications. One possible risk associated with cannulation is an injury to the superficial branch of the radial nerve. The radial nerve divides to the superficial branch and the deep branch at the top of the forearm, and the superficial branch lies behind the brachioradialis muscle close to the lateral side of the radial artery and terminates the lateral side of the radial artery about 7 cm proximal to the wrist. The segment where the superficial branch of the radial nerve runs side-by-side the radial artery ("run side-by-side segment) is an increased risk area of nerve injury. We studied 100 volunteers to measure a "safe" segment (the length between the styloid process and the distal edge of the "run side-by-side segment), using an ultrasonograph. The 95%reference interval (which indicates the central 95% of a reference population) of the "safe" segment was 6.8-11.6 cm [with the mean 9.4 (standard variation: 1.7)] in men, and 5.4-11.0 [8.2 (1.4)] cm in women. In conclusion, we have shown that the margin of safety for needle puncture of a radial artery is about 6.8 cm from the wrist for in men, and 5.4 cm from the wrist for in women.

Prediction of failed facemask ventilation: new scoring system for difficult airway.

BACKGROUND: We previously have shown that there was a strong correlation between failed facemask ventilation, failed ventilation through a supraglottic airway, and difficult tracheal intubation. The primary aim of this study was to evaluate whether or not an established method to predict difficult ventilation through a supraglottic airway was also useful for predicting failed facemask ventilation. METHODS: This was a single-center, retrospective observational study. We studied 28,081 anesthetized patients in whom ventilation through a facemask, and supraglottic airway was attempted as the initial technique during induction of anesthesia, between May 2011 and March 2016. For each patient, the score which had been validated to be useful for predicting difficult ventilation through a supraglottic airway was calculated. The score ranged between 0 and 7 points, and we defined a low risk when the score was 0-3, and a high risk when the score was 4-7. To measure and compare the predictive accuracy of the score, we generated a receiver operating characteristic curve and compared the area under the curve (AUC). RESULTS: The incidence of failed facemask ventilation was significantly higher in patients with high-risk predictive score than in patients with low-risk predictive score [0.38% vs 0.056%, odds ratio 6.8 (95% CI 2.6-18.1, p value = 0.002)], and the sensitivity of the score was 25%, while the specificity was 95%, with a negative predictive value of 99%. The AUC of the score was 0.71 (95% CI 0.58-0.83). CONCLUSIONS: The predictive score for difficult ventilation through a supraglottic airway is also useful to predict failed facemask ventilation.

Rocuronium Bromide Intravenous Solution Maruishi® is more suitable than ESLAX Intravenous® during rapid-sequence induction of anesthesia.

PURPOSE: Rocuronium Bromide Intravenous Solution® (Maruishi Pharmaceutical Co., Ltd, Osaka, Japan) is a newly developed generic drug and we have noticed that compared with conventional rocuronium formulations [e.g. Esmeron (Eslax), MSD Co. Ltd., Tokyo, Japan], rocuronium Maruishi appeared to cause less pain or withdrawal movement. The aim of this study was to assess the hypothesis that the injection of rocuronium Maruishi causes less body movement than rocuronium MSD does, during rapid-sequence induction of anesthesia. METHODS: Sixty patients were allocated randomly to one of two groups. In one group, rocuronium MSD was used and in the other group, rocuronium Maruishi was used. After induction of general anesthesia, a test drug (containing rocuronium) 0.9 mg/kg was injected. Patient's withdrawal movement was graded with the scale. Primary outcome measure was the incidence of moderate or severe movement after the injection of rocuronium. Secondary outcome measure was the degree of movement between the groups. RESULTS: Moderate or severe withdrawal movement was observed after the injection of rocuronium MSD in 11 of 30 patients (37%) and after the injection of rocuronium Maruishi in 3 of 30 patients (10%). There was a significant difference in the incidence between the groups (P = 0.013, 95% CI for difference 26-28%). The degree of movement was also significantly greater for rocuronium MSD than for rocuronium Maruishi (P = 0.015). CONCLUSION: Compared with rocuronium MSD, rocuronium Maruishi is more suitable than conventional rocuronium formulations, for rapid-sequence induction of anesthesia.